Modular lighting systems can be used to provide customized lighting. The number of lighting modules and their assembly can be varied to provide a certain desired illumination. In such lighting modules, a matrix of light sources, such as light emitting diodes (LEDs), is arranged at a board with a certain pitch between the light sources. The pitch may be defined as the distance between the light sources from centre to centre. The smaller and more constant pitch the more continuous illumination is provided from the lighting module. With a smaller pitch, the light sources appear like a single light source (instead of several separate lighting points), when viewed at a shorter distance from the lighting module.
An example of a modular structure of an LED light source is disclosed in US2010/0123380. LEDs are arranged on a circuit board as regular hexagons, with an equal distance between every two adjacent LEDs, such that the modular structure of the LED light source provides uniform illumination.